I don't know what DVI & firewire support is being planned in future models, but I would expect them to take at least another year to trickle down to more players. I'm not personally obsessed with DVI, as I have a progressive scan TV using component 480p, and an LCD computer screen using analog VGA. Both are excellent.
Where I see a greater potential advantage is in a high-resolution digital audio connection, like firewire. This would allow for enormous simplification by sending all the bass management, etc. to the receiver. But there is always some new technology on the horizon; by the time everyone has firewire & DVI, we'll be looking ahead to HD-DVD or something else.
Because of the continual feature-obselecense of these products, I think it's a good idea to stay away from top-of-the-line. Get a Denon 2200 or 2900 today, and by the time you get a nice firewire receiver and a DVI HDTV, you can pick up a cheap DVD that is purely a digital transport. Besides, if you jump straight into the top-of-the-line, you won't have much to upgrade to! Once you live with a low to midrange unit for a year or two, you can form an opinion about what improvements you desire.
-Cooper
